Evaluation of banana peel extract as a natural biofertilizer for enhancing germination and early growth in cucumber (Cucumis sativus) and tomato (Solanum lycopersicum)

Abstract

Banana peel is an underutilized agricultural by-product rich in nutrients and secondary metabolites that may serve as a natural plant growth promoter. This study evaluated the influence of banana peel extract on the germination and early vegetative growth of cucumber (Cucumis sativus) and tomato (Solanum lycopersicum) seedlings. Seeds were treated with varying concentrations of banana peel extract (1%, 3%, and 5%) and compared with a tap-water control. Growth experiments were conducted using 20 mL, 40 mL, and 60 mL extract volumes applied to seedlings for 30 days. Phytochemical screening of aqueous and ethanolic extracts was performed to identify major metabolites. Results showed that cucumber seeds treated with 3% and 5% extract exhibited 100% germination, compared with 40% in the control. Tomato seeds displayed maximum germination (100%) at 3% extract. Cucumber seedlings receiving 60 mL extract demonstrated the greatest shoot length (14.9 cm) and biomass (1.5458 g), whereas tomato seedlings responded most positively to moderate extract volumes (20 – 40 mL). Phytochemical analysis revealed the presence of tannins, flavonoids, alkaloids, saponins, and triterpenoids. The findings indicate that banana peel extract enhances seed germination and early seedling development, highlighting its potential use as a sustainable biofertilizer.